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The electrolyte is one of the main components in a Li-Ion cell/battery. It consists of one or a mixture of organic carbonates (e.g., dimethyl carbonate) together with a Li-ion salt. The heat of combustion of the organic carbonates can contribute between 65-70% of the total energy content in a 18650 Li-ion cell. If a cell is heated, either by an external source or due to short-circuit, it may cause the battery to vent and, under certain conditions, experience thermal runaway. The laminar burning velocity is an essential parameter for flame propagation. It is also an essential input parameter for several computational fluid dynamic (CFD) codes. No experimental studies on laminar burning velocities are currently published for Li-ion electrolytes such as dimethyl carbonate (DMC). In this study, the Markstein length, the laminar flame speed and burning velocity for DMC and propane are determined for an outwardly propagating spherical flame (OPF). The flame was analyzed in a 20-liter explosion sphere with initial conditions at 100 kPa absolute and 300 K. The results from the experiments fit well with previously published results for propane and are slightly lower than theoretical calculation for DMC. Propane has higher laminar burning velocity compared to DMC, which corresponds well with the higher rate of explosion pressure rise for propane. DMC has a higher maximum explosion pressure compared to propane.